Heat sink assembly

ABSTRACT

An exemplary heat sink assembly includes a base plate for thermally contacting an electronic component and fins protruded from the base plate to dissipate heat transferred from the base plate by nature convection and thermal radiation. A heat conductive film is formed on an outer surface of the heat sink. A thermal radiation wavelength region of a far and middle infrared ray is located in a thermal radiation wavelength region of the heat conductive film.

BACKGROUND

1. Technical Field

The present disclosure relates to heat dissipation apparatus, and more particular to a heat sink assembly dissipating heat generated from electronic components.

2. Description of Related Art

With a rapid development of electronic products, heat generated from electronic components of the electronic products become more and more. If the heat can not be removed rapidly, the electronic components are prone to be overheated. Generally, a heat sink and a fan are provided to dissipate heat generated from the electronic components. The heat sink is mounted on the electronic component and the fan is mounted on the heat sink. However, the electronic products become thinner and thinner, and a space in each electronic product is small. The conventional heat sink and the fan have a larger bulk, and are not suitable to the electronic product now.

What is needed, therefore, is an improved heat sink assembly which can overcome the above described shortcomings

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a heat sink assembly according to an exemplary embodiment of the present disclosure.

FIG. 2 is a cross-sectional view of the heat sink assembly of FIG. 1 taking along line II-II thereof, wherein the heat sink assembly contacts an electronic component.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, a heat sink assembly 1 according to an exemplary embodiment includes a heat sink 10 and a heat conductive film 30 formed on an outer periphery of the heat sink 10.

The heat sink 10 is integrally formed by a material having good heat conductivity coefficient such as copper, aluminum, or an alloy thereof. The heat sink 10 includes a base plate 11 and a plurality of fins 13 protruded from a top surface of the base plate 11. The base plate 11 is a rectangular plate with a uniform thickness and a central portion of a bottom surface thereof is used to contact an electronic component 20 to absorb heat generated from the electronic component 20. Each fin 13 is an elongated strip and perpendicular to the top surface of the base plate 11. The fins 13 are spaced from and parallel to each other. The fins 13 dissipate heat transferred from the base plate 11 by nature convection and thermal radiation.

A heat conductivity coefficient of the heat conductive film 30 is higher than that of the heat sink 10. A heat resistance of the heat conductive film 30 is lower than that of the heat sink 10. The heat conductive film 30 entirely covers the heat sink 10, and is thinner than the base plate 11 and the fin 13. The heat conductive film 30 is formed by metallic oxide, such as aluminum oxide, magnesium oxide, titanium oxide, or a combination thereof, and can radiate heat absorbed by the base plate 11 rapidly and evenly.

In use, a part of the heat conductive film 30 formed on the bottom surface of the base plate 11 rapidly absorbs heat of the electronic component 20 and transfers the heat to the base plate 11 and another part of the heat conductive film 30 dissipates the absorbed heat rapidly and evenly.

TABLE 1 shows a relationship between a temperature of the electronic component 20 and a thermal emissivity of the heat sink 10 with a size of 42 mm*42 mm*32 mm(length*width*height).

TABLE 1 Thermal Emissivity of heat 0 0.2 0.4 0.6 0.8 1.0 sink 10 Temperature of electronic 89.4 84.9 80.7 81.0 79.4 78.1 component 20 (° C.)

According to the tested conclusion of TABLE 1, the temperature of the electronic component 20 decreases following the increase of the thermal emissivity of the heat sink 10. When the heat sink 10 coated by the heat conductive film 30 to form the heat sink assembly 1, the temperature of the electronic component 20 is 79.7° C. Thus, the thermal emissivity of the heat conductive film 30 is varied between 0.8 to 1.0. A thermal radiation wavelength region of the heat conductive film 30 is varied between 2.5 micrometers to 1000 micrometers. A wavelength region of a far and middle infrared ray is 2.5 micrometers to 1000 micrometers. The wavelength region of the far and middle infrared ray is located in the thermal radiation wavelength region of the heat conductive film 30. Therefore, the heat conductive film 30 can radiates heat of the far and middle infrared ray rapidly by thermal radiation. Thus, the heat radiation efficiency of the heat sink assembly 1 of the present disclosure is improved relative to the conventional heat sink having no heat conductive film 30. The heat dissipation efficiency of the heat sink assembly 1 is improved.

It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed 

What is claimed is:
 1. A heat sink assembly, comprising: a heat sink adapted for thermally contacting an electronic component; and a heat conductive film formed on an outer surface of the heat sink, a thermal radiation wavelength of the heat conductive film being located in a far and middle infrared ray wavelength region.
 2. The heat sink assembly of claim 1, wherein a heat conductivity coefficient of the heat conductive film is higher than that of the heat sink.
 3. The heat sink assembly of claim 1, wherein the heat conductive film is formed by metallic oxide.
 4. The heat sink assembly of claim 3, wherein the heat conductive film is formed by aluminum oxide, magnesium oxide, titanium oxide, or a combination thereof.
 5. The heat sink assembly of claim 1, wherein a thermal emissivity of the heat conductive film is varied between 0.8 to 1.0.
 6. The heat sink assembly of claim 1, wherein a thermal radiation wavelength of the heat conductive film is varied between 2.5 micrometers to 1000 micrometers.
 7. The heat sink assembly of claim 1, wherein the heat conductive film entirely covers the outer surface of the heat sink.
 8. The heat sink assembly of claim 1, wherein the heat sink is integrally formed by aluminum, copper or an alloy thereof.
 9. The heat sink assembly of claim 8, wherein the heat sink comprises a base plate and a plurality of fins protruded from a side of the base plate.
 10. A heat sink assembly, comprising: a heat sink comprises a base plate adapted for thermally contacting an electronic component and a plurality of fins protruded from the base plate to dissipate heat transferred from the base plate by nature convection and thermal radiation; and a heat conductive film formed on an outer surface of the heat sink, a thermal radiation wavelength of the heat conductive film being in a range from 2.5 micrometers to 1000 micrometers.
 11. The heat sink assembly of claim 10, wherein a thermal emissivity of the heat conductive film is varied between 0.8 to 1.0.
 12. The heat sink assembly of claim 10, wherein a thermal radiation wavelength of the heat conductive film is varied between 2.5 micrometers to 1000 micrometers.
 13. The heat sink assembly of claim 10, wherein the heat conductive film entirely covers outer surfaces of the base plate and the fins.
 14. The heat sink assembly of claim 10, wherein the fins are spaced from each other and parallel to each other. 